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The windscreen wiping system is mandatory requirement for automotive vehicle as per Central motor vehicle rules (CMVR). The main scope of the standard is to ensure vision zones to be wiped by wiping system to ensure maximum field of vision to the driver. The evaluation of vision zones as per IS 15802:2008 is generally determined by virtual simulation by OEMs. The limitation of virtual simulation is due to actual tolerances in vehicle, due to seat fitment, ergonomic dimensions, seat cushioning effect and wiper non-effective operation which are not taken into consideration very well off. The testing methodology described in the paper is an in-house developed test method based on SAE recommended practices. With the help of 3D H-point machine and a laser based ‘Theodolite’ equipped with horizontal and vertical angle projections from single pivot point is used to develop various vision zones on an actual vehicle windscreen as per technical data.

In high speed race cars, aerodynamics is an important aspect for determining performance and stability of vehicle. It is mainly influenced by front and rear wings. Active aerodynamics consist of any type of movable wing element that change their position based on operating conditions of the vehicle to have better performance and handling. In this work, front and rear wings are designed for race car prototype of race car. The high down force aerofoil profiles have been used for design of front and rear wing. The first aerodynamic analysis has been performed on baseline model without wings using CFD tool. For investigation, parameters considered are angle of attack in the range of 0-18° for front as well as rear wing at different test speeds of 60, 80, 100 and 120 kmph. The simulation is carried out by using ANSYS Fluent. The simulation results show significant improvement in vehicle performance and handling parameters.

Any change is vehicle exterior design, affects the aerodynamics characteristic. Generally different types of roof racks are attached on passenger vehicles to carry luggage which affects aerodynamic drag. The objective of this work is to perform aerodynamic analysis of ground vehicle with roof rack to investigate the change in drag coefficient. First, the aerodynamic analysis of a baseline passenger car model is performed with and without generic benchmarked roof rack at 100 kmph. Further analysis is carried out with different new designs of roof racks. Based on simulation result, a scaled down prototype model is fabricated and validated by using a wind tunnel test for optimum suitable case. The modelling of the vehicle is done in CATIA tool and simulation is carried out by using ANSYS Fluent.

With introduction of Bharat Stage VI (BS VI) norms from 1st April 2020, automotive industry will observe one of most stringent Indian emission regulation implementation in line with International standards. The Bharat Stage VI (BS VI) regulation also mandates for Real Driving Emission (RDE) measurement from 1st April 2020 for data collection and subsequently establishment of RDE compliance Factor (CF) by 1st April 2023. Indian RDE test procedure will be largely based on European RDE with minor changes in terms of climatic conditions, traffic pattern, speed limit, topography, and vehicle population. For performing a successful RDE trial one of the most critical part is selection of a route on which all RDE boundary conditions can be met. This technical paper summarizes the outcome of RDE experiments carried out on Light Duty Vehicles (LDV) in the city of Pune, Mumbai, and Bangalore. The collected data was post processed using CO2 based Moving Average Window (MAW) method.

The design and development of complete vehicle, understanding of chassis system development process is an important task. Chassis frame of a vehicle is supporting member, both structurally and functionally, to all other chassis aggregate systems viz. suspension, steering, braking system etc. In this paper, a methodology for chassis frame model construction and validation is explained. In present work, chassis frame model is validated in terms of modal parameters and also against static loading conditions. Existing chassis 3D Computer Aided Design (CAD) data was generated using scanning and cloud point data conversion technique. FE model was generated and validated through experimental measurements viz. modal testing, vertical bending, lateral bending, and torsional bending test. Loading and boundary conditions were replicated on the complete FE model in CAE domain and test validation was carried out using appropriate mesh biasing and weld modeling techniques.

Occupant motion in a vehicle rollover accident is a function of many factors. Some important ones are vehicle kinematics, position of the occupant in the vehicle, occupant size, ground topology and restraint usage. The far side belted occupants are more vulnerable than the near side occupants in a rollover accident as they have more energy as a result of their trailing and higher side of the vehicle. This outcome is attributable to the inadequate safety performance of the conventional single loop; B-pillar mounted D-ring restraints. Roof crush tends to displace the vehicle's B-pillar, resulting in D-Ring displacement which causes slack in the lap portion of the restraint. This slack enables centrifugal loads to move the far side occupant further away from the vehicle's instantaneous point of rotation. In this scenario, the presence of any ejection portal can result in an occupant becoming partially or fully ejected.

An open wheeled open cockpit high speed car with 800 CC MPFI engine was developed validated and run at 105 kmph. The key focus was to build a car with superior aerodynamic characteristics especially in terms of drag. This work discusses in detail about the design and simulation of car using CFD package followed by Wind Tunnel testing. The design of high speed car starts with design of seat according to the ergonomics of the driver followed by the space frame. Based on the space frame designed, the body panels are sketched and CAD model is developed. The CAD model is imported in CFD package for virtual testing and validated through wind tunnel results. For this 1:3 scale model was manufactured using Rapid Prototyping.